Currently, there are several different one- and two-wire interface definitions, such as Inter-Integrated Circuit (I2C), System Management Bus (SMBus), SensorPath, and Universal Asynchronous Receiver/Transmitter (UART). Each of these interfaces, however, suffer from several common drawbacks. Multiple identical devices usually cannot be coupled “on” the bus at the same time. The host controller (master) usually addresses the slaves on the bus so each slave has a unique “bus address” so as to access each slave individually. This is normally achieved by using different device variances with different factory trimmed bus addresses, by using address pins on the devices, or by using special “address assignment protocols” (like in the SMBus). Additionally, issuing alerts by the slaves to the master controller usually requires additional pins and connecting wires. Therefore, there is a need for a serial interface that addresses the shortcomings of other conventional serial interfaces.
Some examples of conventional designs are: U.S. Pat. Nos. 5,862,354; 7,099,970; 7,103,008; 7,587,539; 7,802,036; and U.S. Patent Pre-Grant Publ. No. 2008/0215780.